Finishing machine



5 Sheets-Sheet l March 3, 1959 J. W.TH1EME ET AL FINISHING MACHINE FiledJune 27, 1955 March 3,1 1959 J. w. THIEME ET AL FINISHING MACHINE 5sheets-smet 2 lFiled June` 2'7, 1955 .MJ n 5% M "631. Mama/a... u E wwwM v @www .w M .A JM w u y ma i /J y, y p M.

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March 3, 1959 J. w. THIEME TA1` 2,875,676

FINISHING MACHINE Filed June 27, 1955 5 Sheets-Sheet 4 4: roe/vaas'. Y

March 3, 1959 J. w. THIEME ET AL A'2,875,576

FINISHING MACHINE V Filed June 27, 1955 5 sheets-sheet 5 United StatesPatent() FINISHING MACHINE John W. Thieme, West Compton, and Patrick J.`McDonn ell, Compton, Calif.; said Patrick J. McDonnell, assignor to saidJohn W. Thieme Application June 27, 1955, Serial No. 518,088

13 Claims. (Cl. 94-45) The invention relates to machinery for workingsoft concrete and has particular reference to a rotary machine poweroperated and manipulated by hand by use of which poured concrete can betroweled and later finished by use of the same machine adjusted in anappropriate manner.

Up until a few years ago almost all concrete was finished by hand. Thelaying of concrete roadways later gave rise to use of power operatedequipment for screeding the surface of the roadway but even here finaltroweling and finishing up until relatively recent times has been doneby hand.

It has been learned through studies with respect to hand labor methods,particularly Where the hand labor work is of a heavy character such asis the troweling and finishing of concrete slabs, that a tremendousamount of time may be needed for such operations to the point where theexpense of troweling and finishing considerably overbalances the cost ofmaterial `and other operations in connection with the laying of theslab. These circumstances have given rise to the design and constructionof a certain line of power operated concrete surfacing machinery whichhas resulted in the placing upon the market of some four or five rotaryactuated finishing machines wherein the blades are driven usually by agasoline engine and the machine manipulated over the slab by hand. Thesemachineshave followed a substantially uniform pattern in that they havecomprised ing blades rotate.

a carriage on which is mounted a small, low horse-power,

gasoline engine below whichiis a housing or rotating head. On the headare radially extending blades, the blades being so mounted that they canbe tiltably adjusted in order to produce a greater or lesser degree ofworking of the soft concrete, depending upon what surfacing operation isdesired by the installer.

Another common feature of such machines is the employment of a rathersimple, conventional clutch arrangement designed to take hold to agreater or lesser degree depending upon the speed of operation of thepower unit.` Hence, the expedient has been to provide a throttle controladapted to be manipulated by the operator so that by opening or closingthe throttle and hence varying the speed of the engine, the speed ofrotation of the blades can be controlled. A serious disadvantage of thistype of device is that the gas engine can never be started unless anassistant operator holds the handle by which the device is manipulatedsince otherwise as soon as the engine is started the handle will beginto whip around while the blades remain fixed in position upon theconcrete. The same disadvantage follows through in operation of thedevice under those circumstances wherein should an obstruction be hitand the operator lose his grip upon thehandle, the blades will setthemselves in the concrete and the handle will whiparound until someobstruction is thrown in its way to stall operation of the engine.

Another and serious disadvantage in machines hereto-` fore placeduponthe market is'an open construction of j 2,875,676 Patented Mar. 3,1959 the operative parts which permits wet concrete to lodge in manydifferent places wherein unless completely and thoroughly washed theconcrete tends to set, gradually accumulating and clogging the machineryas well as adding its weight to the normal weight of the machine. Inaddition to the clogging the action of concrete in setting up has had a'serious deteriorating effect upon those portions of the mechanism whichhave been exposed.

In devices of the prior art guards have of necessity been providedenclosing the area within which the trowel- This has been essential forsafety purposes. In most instances the guards thus provided have beenemployed as a tilting support for` the outer ends of the blades.Although constructed in this fashion the guard serves its purpose as aguard, nevertheless, by reason of the fact that it must rotate as theblades rotate, the guard itself has a tendency to climb upon`obstructions and form Work near edges of slabs being worked upon andhas been very prone to throw the entire machine out of alignmentcreating often a dangerous condition when a rotary surfacing machine atfull speed chances to climb up on the form work.

Although numerous attempts have been made by the prior art to provide aready means of changing the tilt adjustment of the blades thereby toincrease or diminish friction of the blade-on the soft concrete and itsability to work the surface of the` concrete, `such adjustments haveoften been designed in such fashion that they can be made only when themachine is stopped and in those few occasions where the adjustment isattempted as an` making it one capable of manipulation without unduefatigue to the operator.

Another object of the invention is to provide a new and improved rotaryconcrete surfacing machine which is compact in its design andconstruction to the end that virtually all moving elements are housingor con-4 cealed and thus protected from the action of wet concretemaking the device one easy to clean and easy to maintain in properworking condition and with a greater safety factor for the operator.

Still another object of the invention is to provide a new `and improvedrotary concrete surfacing machine constructed in a manner such that thegear train and a power means for adjusting the -blades are mounted andhoused in a hermetically sealed casing wherein lubricant `for the geartrain is employed simultaneously as a hydraulic iiuid adapted whendesired to be sent to a hydraulic motor for adjusting the blades andwhich when not used for that purpose can lbe readily by-passed withoutloss of efciency to continue its function as a gear lubricant.

Still another object of the invention is to provide aA new and improvedpower means for adjusting the tilt the hydraulic means being so arrangedthat it can be manipulated from the ends of the handle by fingertip'` jcontrol.

Further among the objects of the invention is to provide a new andimproved power actuated manuallymanipu latable concrete surfacingmachine suitably,I provided with stationary guards collapsible foreasy.shipping and whichl are to a great degree safety factors, the inventionhaving forits object to further provide an adjustable'handle controlwhich can be manipulated at any time, whether the machine is .in.operation ornot, from a free end of the handle, the adjustment ofhandle height being .convenientlymounted also with relation `to athrottle control and ,acontrol for the blade adjustment so that the.operator has complete control over the machine from the handle at all.times.

.Still another object of the .inventionis to provide a new and saferclutch control that does not depend on varying engine speeds to `controlrotation-of the blades, and that automatically ydisengages should theoperator ylet go or lose control of the handle while operating themachine.

With these and other objects in view, the invention consistsin theconstruction, arrangement and combination ofthe various parts of kthedevice whereby the objects contemplated are attained, as hereinafter setforth, pointed outin the appended claims .andillustrated-,in theaccompartying. drawings.

In the .drawings Figure l isa vertical `sectional view ,of the device.

Figure 2 is a fragmentary sectional view on the line 2--2 of Figure 1.

Figure` 3 is a cross-sectional View of thedevice taken on `theline 3--3of Figure l.

-Figure 4.is .a view illustrating in detail the 'hydraulic circuit Vwiththehydraulic pump shown partially .in section and showing adjacentportions of the machine in phantom view.

Figure 5 is a view partially in section showing details of .thehydraulic valve taken on the line 5-5 of Figure 4 and details of themanual adjustment of the hydraulic valve which exists at the outer endof the handle.

Figure 6 is a longitudinal sectional View of the hydraulic motor foroperating the blade adjustment taken on the line 6-6 of Figure 4.

Figure 7 `is a fragmentary lsectional view'of a portion of the'hydraulicpump taken on the line77 of'Figure 4.

VFigure'S is a cross-sectional view taken on the line 8 8 of Figure 1showing the several controls at the end of the handle.

Figure 9 is a sectional view `taken on the line99 of Figure 8 showingfurther details of the control and particularly the clutch control.

Figure 1 0 is an elevational view partially in section showing amodified type of drive mechanism.

Figure l1 is a sectional view showing a modified form of hydraulic meansfor lhand manipulation to adjust the tilt of the blades.

Figure 12 is a longitudinal sectional View taken on the line 12--12 ofFigure 11 showing valving of the manually actuated hydraulic adjustingmeans.

In an embodiment of the invention chosen for the purpose of illustrationthere is shown a rotary concrete surfacingmachine comprising a casingindicated generally 'by "the reference Vcharacter 10, a conventionalpov/'er source .'11, the base of which is 'shown lmounted on the casing"10, a housing 12 below the casing and adapted to carry blade assemblies13, 14 and 15, and a handle asn sembly'16. A ring `guard 17 is mountedupon legs 18, 19, 20 vand 21 to support the guard in a position belowthe casing A and surrounding the outermost ends of the blades.

As suggested in Figure 3 the guard may be built in two semi-circularhalves joined by a Vbar 54. A rivet 555ecuresthe bar to one half and aremovable piu 56 'secures the'bar to .the other half.

`More particularly the casing .consists of an upper vhalf 22 and a lowerhalf 23 hermetically sealed at their opposing edges and adapted to bebolted together by means of a number of appropriately spaced bolts 24,one of which is shown in Figure l passing from the upper half 22 intotheilowerfhalf 23. The upper :and lowerhalf of the casing when bolted:together `form a chamber .25. A conventional power source 11 may, forexample, be a low horsepower gasoline engine of the type currentlyemployed on a great variety of small hand manipulated but power actuatedmobile tools. The power source is equipped with a drive shaft 26 whichextends downwardly through a eld passage 27 into the chamber 25.

ln the embodiment illustrated in Figure l a pinion 28 is non-rotatablysecured to the drive shaft 26 by the aid of a key 29 so that the pinionrotates with the drive shaft. The pinionl meshes with and is adapted todrive a large gear 3h. The large gear is mounted upon a gear shaft 31,the shaft being mounted lby means of a bearing t 32 in the upper half22of the casing and by means of a bearing 33 in the lower half 23 of thecasing. 1n the embodiment shown the large gear 3d is free to move withrespect to the gear shaft 31, the gear being one provided on its lowerside with a clutch indicated generally by the reference character 35.

`By yway of example .only the clutch 36 is shown as a cone clutch withva cone clutch face 36 forming the inside face of V'a clutch wall 37andthecone clutch element 38 being .adapted to enter the cone clutchface by movement upwardly.

The cone clutch element is non-rotatably secured to the gearshaft 31 bymeans of a key 39 so that when the cone clutch lelement is rotated thegear shaft 31 rotates and causes a pinion 40 to rotate because of thepinion being nonfrotatably secure-d to the gear shaft by means of a key41. The pinion in turn meshes with a gear 42 of large circumference.Thegear 42 as well as the pinion 40 lies in a well 43 at the bottom ofthe chamber 25. It will be noted that the gear 42 is non-rotatablysecured to a stub shaft 44 at the gear hub 45. The stub shaft isd'ireadedly secured .to a hollow driven shaft 46, the hollow drivenshaft being rotatably mounted in bearings 47 and 48 in a boss 49 on thelower side ofthe casing 1t?.

The housing 12 is provided with a head Si) by means of which the housingis non-rotatably mounted upon the hollow driven shaft 46 by reason ofinterposition of a key 5.1.

The wall of the housing 12 provides a closed gear pocketSZ hermeticallysealed by application of cap screws 5.3 whichmount the head 50 on thehousing. From the foregoing explanation it will become evident that whenthe power source 11 is operated and the clutch 35 is engaged, the powersource acts through the drive shaft 26. The gears within the casing 1t),and the driven shaft 46 will rotate the housing 12 and the blades whichare mounted thereon.

Invt'he chosen'embodiment ofthe invention the housing 12 is providedwith horizontally extending bosses 60, three in number, to accommodatethe blade assemblies 13, 14 and 1.5. An inner blade shaft 61 is mountedat an inner end 62 rotatably in the wall of the casing and at lanotherapertured end 63 is `rotatably mounted with inthe boss Gil. An outerblade shaft 64 is non-rotatably secured to theinnerblade shaft by .meansof a key 65. Packing 66 `retained by apacking nut 67 seals the gearpocket 52 where thebladeshafts emerge.

-On each'of lthe outer blade shafts 64 is a combination troweling andservicing blade 68 secured to and below the respective blade shafts bymeans of brackets 69. Adjusting screws 70 and 71 extending through theblade shafts 64 and into the bracket 69 may be employed to secure the-blade to the blade shafts and to adjust it in place. Gears 57 and 58 ontheir respective shafts 61' mesh with a gear 59 on the shaft 61 so thaton tilting all will -tilt in the same .relative direction in response toan appropriate adjusting device.

For lubricating the gears and pinions which lie within the chamber 25and interconnect the drive shaft 26 and hollow dri-ven shaft 46 there isprovided a bath of lubricating liquid which is adapted to ll the well 43and if need be a portion of the chamber 25 above the top ofthe well.kSince the chamber .is hermetically sealed,

there is no need to add lubrication from time to time.

The lubricating Huid at the same time serves as a hy- .draulic Huid in ahydraulic pump and motor system em- -pump 75 mounted in the chamber 25by means of a bracket 76 secured to the inside of the chamber wall. Thepump 75, as best illustrated in Figure 4, has a pump chamber 77 and apump rod 78 reciprocatably mounted therein. The pump rod has a head 79engaged by a roller 80 of a walking beam 81. The beam is pivotallymounted by means of a shaft 82 upon the bracket 76. To give the motionneeded to the walking beam 81 in order to reciprocate the pump rod 78the clutch wall 37 previously referred to is eccentrically shapedl sothat an outer surface 83 is eccentric'with respect to the axis ofrotation and when the surface 83 is rotated in contact with a roller 84on the walking beam, the walking beam will be rocked once in eachdirection for each rotation of the large gear 30. This actionreciprocates the pump `rod 78 and causes the pumping action in the pump75.

A pump intake line 84 has an inlet 85 located in the well 43 andincidentally at a position adjacent the top surface of the pinion' 40.The intake line 84, as illustrated in Figure 7, is directed past a ballcheck 86 into the pump chamber 77. As the pump rod 78 reciprocates fromleft to right, as viewed in Figure 7, liquid is drawn into the pumpchamber. When the pump rod 78 moves from right to left, as viewed inFigure 7, the ball check 86 is seated and hydraulic liquid, which isalso incidentally the lubricating liquid, is forced past a ball check 87into and through a hydraulic power line 88 to a three-way valve 89.Interior details of the three-way valve 89 are illustrated in Figures 4and 5.

The three-way valve is of substantially conventional construction and isadapted to tne needs of the device here under consideration. The Valveconsists of a valve body 90 secured by appropriate conventional means tothe wall of the chamber 25 near the side of the chamber to which thehandle assembly 16 is attached. The body provides a valve chamber 91within which a valve element 92 is adapted to reciprocate and to occupyany one of three different positions. In one operative position of thevalve hydraulic liquid under pressure from the power line 88 travelsthrough an inlet branch 93 to the valve chamber 91. It can be assumedthat for the purpose of description the valve element 92 is in neutralposition, namely, the solid line position of Figure 5. The inletopening, not shown, for the inlet branch 93 is so positioned withrespect to a reduced portion 94 on the valve element that hydraulicliquid under pressure will be by-passed upwardly and outwardly through abypass line 95 which is so positioned that it leads the bypass liquid toa location above the top of the gear train so that while the liquid isbeing by-passed it` is drained over the gears and pinions for thepurpose of lubrication.

When, for example, the hydraulic liquid is lto be used for adjusting thetilt of the blades, the valve element 92 may be set in a positionnearest the left end ofthe valve chamber to which position it may bemoved by operation of a valve lever 100 from the solid line position ofFigure to a broken line position 100 thereof. When the valve element isin the position last delined, hydraulic liquid under pressure from thehydraulic power line 88 and inlet branch 93 will be directed to ahydraulic line 101 which connects to a fitting 102 by means of which, asshown in Figure 6, hydraulic liquid under pressure can be passed througha passage 103 into a chamber 104 of a hydraulic motor. In addition tothe chamber 104 which in effect is the interior of the hollow drivenshaft 46 the motor consists of a piston 105 reciprocatably mounted inthe chamber 104 to which is attached a piston rod 106 which extendsdownwardly in sliding relationship through a sleeve 107 into the gearpocket 52.

Because of the fact that the hydraulic motor comprising the parts justdescribed must rotate with the driven shaft and the housing 12, thetting 102 previously described must be a rotary fitting suitablyconstructed and packed in accordance with accepted practices and suchthat a portion 102 extending downwardly is rotatably mounted in abearing 102l and the portion of the tting connected to the hydraulicline 101 may as a consequence remain in fixed position while the shaft44 and gear hub rotate.`

Details of the hydraulic motor parts just described are best illustratedin Figure 6. As there shown the piston rod 106 has a crank 110 attachedto its lower end.

On the lower end of the crank is a stub shaft 111 rotatably secured tothe crank and having a pin 112 fas-` moves up and down, the blade shaft64 will be rotated a corresponding amount and, in the exampleillustrated in Figure 6 by the broken line position, when the piston rodis moved downwardly so that the crank occupies the broken line position110', the blade 68 will be tilted to the broken line position 68. Thisis a considerable degree of tilt and would be an adjustment adapted fortroweling. It will be clear from the foregoing explanation of operationof the hydraulic circuit that hydraulic power generated by the pump whenthe motor or power source is in operation can be directed bymanipulation of the three-way valve so that liquid flowing into themotor chamber 104 can force the piston head 105 downwardly, therebyforcing the piston rod 106 down-` wardly to make the adjustment justdescribed. The downward force will tend to build up tension in a spring113 so that when hydraulic pressure is released the spring will assistin returning the piston rod 106 and piston head upwardly aiding thetendency of the force of material against the blades 68 to tilt theblade and cause a similar movement upwardly of the piston rod 106.Interconnection of pinions 57,58 and 59 causes all blades to rotatesimultaneously to the same extent. Further details of the bladeadjustment are shown in Patent No. 2,468,981.

To release the blades for return to initial position the lever 100 ismoved from the broken line position 100' to the broken line position100, as illustrated in Figure 5. This causes the-valve element 92 toshift from left to right to the end of its stroke. `At the end of itsstroke the valve element makes contact between a hydraulic return line114 leading from the fitting 102 to the valve chamber 91. Fluid from thereturn line is passed through the chamber 91 to the by-pass line 95 andthence over the gears and pinions in the manner previously described.For convenience in valving when the blades are not being adjusted andthe hydraulic system is running idling, the power line 88 may bedirected through an idler branch 115 and thence through the bypass line95. This by-passing may also be operated if preferred simultaneouslywith the by-passing of return Huid from the hydraulic motor through thereturn line 114.

For manipulating the three-way valve there is provided a valve controllever 116. Normal or idler position of the hyldraulic system is ineffect when the valve control lever 116 is in the solid line positionillustrated in Figure 5. The control lever is immediately adjacent acrossbar 117 of the handle assembly so that the blade adjustment can bemade by thumb or finger pressure upon the control lever at any time. Thecontrol lever is pivotally mounted by means of a pin 1181 in a shaft 119of the handle assembly. A lower end 120 of the control lever isconnected by means of a toggle 121 to a cable 122, whichcable runsthrough a packing gland 123 to a toggle 124 by means of which it isattached to the lever 100. i

:So-.that the 'hydraulic'system .may not .be overloaded withpressure atlhigh Speeds ofrotationof the sourceof .power there is provided a reliefvalve v125, asv illustrated Ain Figure 7, spring loaded so that excesspressure will Causehydraulic fluid to be relieved through a neck 126 .aslong as the'excess .pressure prevails.

.The clutch element 38 previously referred to is manip- .ulated .by aclutch lever 130 mounted adjacent and in frontof the crossbar 117.Abracket 131 may be provided for mounting th-e clutch lever on thehandle shaft 119. The clutch lever 130, as best illustrated in Figure 9,iSv-provided with a .composite pivotal mounting so that a slightmovement of the clutch lever by theexertion of relatively little handpressure is capable of being multiplied. a suitable extent through alinking lever 132, whereby the movement is transferred ,through a toggle133 to -aclutch cable 134 which passes through yan appropriate packinggland inthe casing, not shown, toa position Where,v as shown in Figure3, the clutch cable connects to aclutch control 135. T .e clutchco-ntrol includes a clutch control shaft 136 which is rotated byreciprocation of the clutch cable 134, thereby to rotate a clutcheccentric 137.in a direction such that pressure is exerted upon a plate138 when the clutch is to be disengaged and released from the plate whenthe clutch is to'be engaged. As shown in Figure l, a clutch spring 139tends to raise the plate 13S and a sleeve 144i, thereby to elevate'thecone clutch element 38 moving it into engagement with the cone clutchface 36. For disengagement a spring 141 tends to rotate the clutchcontrol shaft 136 in an opposite direction causing the eccentric topress upon the annular plate 138, thereby to disengage the clutch. Ashort .link 142, not referred to previously in connection withmanipulation of the clutch lever 130, makes possible the delicatemovement of the clutch lever to .engage and ldisengage the clutchwithout apparent effort on the part .of the operator. Although amechanical control has been shown and described for the clutch it willbe appreciated that other power means such as a hydraulic control may besubstituted.

To further facilitate operation of the device a throttle control or gascontrol lever 145 is mounted on the end of the handle shaft 119immediately adjacent the valve control lever 116. The throttle controlleverlies adjacent a crossbar 146 so that it can be readily operated bythethumb or fingers of the left hand of an operator as it rests-upon thecrossbar 146.

:Circumstances may arise where itmay be desirable tofemploy a handoperated hydraulic vpower system for adjusting the position oftheblades. As shown in Figures ll and l2 this may be accomplished bylocating a hand actuated pump 150 in the handleshaft adjacent thecrossbar 117. The pump maybe supplied with ya pump handle 2151 pivotallymounted on a bracket 152 in the same relativelocation as the.valvecontrol lever 116 previouslyfdescribed. The pump may comprise a.barrel 1.53 formingapump .chamber154'within .which a pump rod l155 .isreciprocatably mounted. Packing156is supplied ,for the inner end v.of`the rod sufficient to make `a Seal. When hydraulicliquidunder pressureis to be supplied to the same motor previously described, the pumpl1andle151 is reciprocated. As the pump rod1'55 is moved from right toleft, as viewed in Figure l2, iluid is drawn inwardly from a reservoirV170 located in .the handle, througha passage 171, and then through aninlet 1577 past a check valve 153 into the chamber 154. When the :rod.is moved `from left to right, as viewed :in vthe same Vfigure, ytheball check `153 will kseat and oil will be `forced past a ballcheck 159through an `outlet passage 316i) through an oil pressure :supply line161 to .the fitting 102. The pump handle canbe pumpedas much as neededto tilt the position of the .blades .a desired amount. .Pressure appliedto :the chamber 104 acts against the piston 105 and against .the tensioninthe springll in the same manner as previously described.

vbe omitted.

V8 When the tilt of the `blades is .to .beadjusted tota lesser degree, arelease valve .165 is unseated byrotation of 1a valve handle 166 whichwill .permit built-up `pressurein the passage to be relieved past a ballcheck ."167to a release passage 168.

Occasions may arise where it becomes undesirable'to .employ the gearsystem shown and described in connection with Figures l and 2. In suchevent a .belt Vdriven drive train may oe employed, as illustrated inFigure l0. rl`he belt drive train maybe used in the same casing f10which is used for the gear train. As shown thereislconnectedl to thedrive shaft 26 a pulley 175 over .whichxa .V-.belt 176 is passed in .asuitable groove 177. The V-belt connects with a large pulley 178v,provided with a similar .groove 179. Rotation of the pulley 21178 ispassed through the clutch 35 in the samemanner as .previously .describedwhereafter a pulley 18() keyedto .the shaft 31 in place of the pinion,previously described, receives a belt 181 in a kgroove 182. Thebeltllitransfers .powerto alarge pulley .183 provided with .-a suitablegroove 184 to receive the belt. The large .pulley 183 .in turn is keyedto the shaft 144 .by means of a key "185. The shaft 144 is the sameshaft as has already ;been described and from this point on thestructureof the :belt driven form of the device is the same a has been-.describedheretofore.

vWhen the belt drive is .employed as .described'inconnection with Figurel0, the bath of lubricating fluid must In that eventthe hydraulic systeminitially described, which depends upon the reservoiroflubricating fluid-for a supply of hydraulic uid, need be.ornitted. Consequently for thebelt driven form of thedevice .the hand operated hydraulic system foradjusting thetilt `of the blades is preferable by making use of aseparatefreservoir such as the reservoir 1'70.

In the operation of machines of the type .herein described it is highlyadvantageous vto be able-to readily lift the device to move it fromonelocation to another. To'facilitate such 4a lifting yoperational hole190 is'provided on the side of the lower casing half Z3 opposite fromthe side to which the handle is attached. A lifting bar 191,afragmentary portion of which is illustrated in Figure l, is adapted tobe inserted into thehole -and by use of the lifting bar in conjunctionwith use ofthe handle in its lowermost position two operatorscan readilylift the entire apparatus. The lifting ,bar may `for .convenience becarried by brackets 19.4 .on the handle-16.

Conditions also arise where a machine -of greater spread may be betterable to perform a desired surfacing voperation in some particular typeof installation. Thede sign and Aconstruction herein described enables`useofthe machine as either athree-foot diameter machine .or lafour-foot diameter machine. When equipped `.initially asa three-footmachine, those changes necessar-y1comprise substitution of a four-footdiameterring `guard :for the original ring guard and replacementof :theoriginal blades 68 .with .corresponding longer blades. The bladefittings such as the inner shaft 61 and thegears may .remain the same.4When the machine-of larger diameter .is desired, a greater weight maybe necessary. Weightc-anbe added to the casing by attaching to theopposite :long sides of the casing additional weights. No.other changein the apparatus is necessary. Consequently the same apparatus can beused as either a high ho1'se-poweror.low horsepower machine.

To attach the weights there areprovided platforms 192 which may beprovided with apparatus .193 Iadapted'to thereception of lead weightsorweights ofcorresponding character which may be snugly held near thecenter .of gravity of the machine, thereby to increase the weight of the.machine to give greater stability when 4higher power is employed.

Should an occasion arise when agpower source -of Adifferent Eperformancemight be desirable, `only zthe ipower source, the drive shaft v26andpinion :28 need'beremoved.

9 for substitution of a heavier or a lighter power source with a similardrive shaft and pinion.

There has accordingly been described herein a compact, effective, rotaryfinishing machine, moving parts of which are well protected andconcealed and which by reason of the mechanical structure involved issafe to operate and easy to manipulate from the operating handle. Thedevice is sensitive to adjustment so that it can be readily set at adesired troweling adjustment, in which adjustment the speed can becarefully controlled and readily shut oif.

While we have herein shown and described our invention in what we haveconceived to be the most practical and preferred embodiment, it isrecognized that departures may be made therefrom within the scope of ourinvention, which is not to be limited to the details disclosed hereinbut is to be accorded the full scope of the claims so as to embrace anyand all equivalent devices.

Having described our invention, what we claim as new and desire tosecure by Letters Patent is:

l. A rotary machine for surfacing concrete comprising a casing forming achamber, a guard extending below the casing, a driven shaft extendingbelow the casing, a housing attached to the driven shaft beneath thecasing, and a handle on the casing, a power plant mounted on the casingand a drive shaft from the power plant extending mto the casing, a powertrain in the chamber interconnecting the drive shaft and the drivenshaft, a plurality of Isurfacing blades extending radially outwardlyfrom said housing and tiltably mounted on longitudinal axes thereof in`said housing and a tilting means interconnecting said blades adapted toalter the adjustment of said blades, said casing including a reservoirof hydraulic liquid associated with the machine, a pump on the machineand in said caslng connected to said reservoir, a pump driving mechamsmoperably connected between said power train and the pump, a hydraulicmotor on the machine having a connection to said tilting means adaptedto effect a tilt ladjustment in said blades, a hydraulic valve on themachine connected to said pump, a hydraulic connection 'from said valveto said hydraulic motor, a hydraulic pressure release connection fromsaid valve to said reservoir, 4and a hydraulic return connection to saidreservoir from said valve adapted to discharge hydraulic liquid fromsaid motor. 2. A rotary machine for surfacing concrete comprismg acasing forming a chamber a hollow driven shaft extending below thecasing, a housing attached to the driven shaft, and a handle extendinglaterally outwardly and upwardly from the casing, a power plant mountedon the casing and a drive shaft for the power plant extending into thecasing, a power train in the chamber interconnecting the drive shaft andthe driven shaft, a plurality of surfacing blades extending radiallyoutwardly from said housing and tiltably mounted on longitudinal axesthereof in said housing and tilting means nter- `connecting said bladesadapted to alter the adjustment `of said blades, said casing including areservoir of hydraulic liquid associated with said chamber, a pumpcarried by the casing connected to said reservoir, a pump drivingmechanism operably connected between said power train and the pump, ahydraulic motor in the driven Yshaft connected through said driven shaftto said tilting .means adapted to effect a tilt adjustment insaidblades, .a hydraulic valve carried by the casing connected to saidpump and having a manual control therefor on said han-` dle, a hydraulicconnection from said valve to said hy- 'draulic motor, and a hydraulicreturn connection to said reservoir from said valve adapted to dischargehydraulic liquid from said motor.

3. A rotary machine for surfacing concrete comprising a casing havingupper and lower halves forming a sealed chamber, an annular guardextending below the casing, a` driven shaft bushing on the lower side ofthe casing having a hollow driven shaft mounted therein, a gear housingattached to the driven shaft beneath the bushing, and a handle extendinglaterally outwardly and upwardly from the casing, a power plant mountedonthe casing and a drive shaft for the power plant extending into thecasing, a speed reducing power train in the chamber interconnecting thedrive shaft and the driven shaft and having anrelement thereof on theupper end of the driven shaft, a plurality of concrete surfacing bladesextending radially outwardly from said housing and tiltably mounted onlongitudinal axes thereof in said housing and a gear train for saidblades interconnected in said housing including means adapted to alterthe adjustment of said blades, said chamber comprising a reservoir forhydraulic liquid, said means comprising a reciprocating pump in thechamber connected to said reservoir, a pump driving mechanism operablyconnected between said power train and the pump, a `hydraulic motormounted in the driven shaft and connected through said driven shaft tosaid gear train, said hydraulic motor having :a connection to the bladesand adapted to effect a tilt adjustment in said blades, a three-wayhydraulic valve in the chamber connected to said pump and having amanual control therefor on said handle, a hydraulic connection from saidvalve to said hydraulic motor, a hydraulic release connection from saidvalve to said reservoir, and a hydraulic return pressure connection tosaid reservoir from said valve adapted to discharge hydraulic liquidfrom said motor, a clutch in said chamber between the drive shaft andthe driven shaft, said clutch being operatively connected with the speedreducing power train, and clutch operating means on said handleoperatively connected to said clutch adapted to engage and disengagesaid clutch at any time.

4. A rotary concrete surfacing machine comprising a casing forming achamber, a power plant on said casing having a drive shaft extendinginto the casing, a bearing on the lower side of the casing having ahollow driven shaft rotatably mounted therein, a gear train in saidchamber including rotating elements connecting said drive shaft and saiddriven shaft and a clutch comprising one of said rotating elements insaid gear train, means forming a reservoir in the lower part of saidchamber for a supply of hydraulic liquid, a reciprocating hydraulic pumpconnected to said supply and a rotating eccentric cam mounted upon oneof said rotating elements the gear train in operating relation with saidpump, a hydraulic valve device in said chamber connected to said pumpand a valve element in the valve device, a by-pass line from said valvedevice directed over said gear train for discharging hydraulic liquid tolubricate said train, a housing mounted on a lower end of said drivenshaft, blades rotatably mounted on said housing on longitudinal axesthereof and in radially outwardly extending position, tilting means onsaid blades in said housing extending radially outwardly of the axes ofthe blades and a common vertically moving adjusting drive for saidtilting means, a hydraulic motor in the casing, a connection 'from saidmotor to said tilting means, a hydraulic power connection from saidvalve device to said motor, and a hydraulic release connection in saidvalve device from said motor to said by-pass line.

5. A rotary concrete surfacing machine comprising a `casing forming achamber, a power plant on said casing having a drive shaft extendinginto the casing, a bearing on the lower side of the casing having ahollow driven shaft rotatably mounted therein, a speed reducing geartrain in said chamber connecting said drive shaft and said driven shaftand a clutch in said gear train, means forming a reservoir for a supplyof hydraulic liquid in the lower part of said chamber, a reciprocatinghydraulic pump connected to said supply and a rotating eccentric cam inthe gear train in operating relation with said pump, a three-wayhydraulic valve device in said chamber connected to said pump and athree position valve element in the valve device, a by-pass line fromsaid valve device directed over said gear train for discharging hy- 1'1draulic liquid to .lubricate said .,train, a gear housing mounted onsaid .driven'shafh blades rotatably mounted on fsaid housing on,longitudinal axes thereof and vinir-adially outwardly extendingposition, gears on said blades in said housing and a common verticallymoving adjusting drive for said gears, a hydraulic motor in the hollowdriven shaft connected through the driven shaft to said adjusting driveand a hydraulic connection from said valve device .tosaid motor, ahydraulic release connection in said valve device from said motor tosaid by-pass line, ,a handle on the casing, operating means on thehandle connected to. said valve element, and a separateoperatingmeanston the handle connected to said clutch.

6. .-A rotarymacbine for surfacing concrete comprisinge casing having aclosed chamber therein, said casing having an upper side and .a lowerside, a power plant mounted 1on said .upper side, a hollow driven shaftmounted on said Alower side in general alignment with said powerplant'and a housing at the lower end of said Shaft .having a closedpocket therein, .radially positioned blade assemblies `tiltably mountedon said housing and extending into said pocket, a common tilting means.for said blades .extending from said blades into said shaft, adrivetrain in said chamber having a connection to said power plant andhaving a connection to said shaft within ,said chamber, a clutch havingan operative connection between opposite ends of said drive train andmounted within said chamber, a .hydraulic pump, pump actuating means.operatively connected between said drive train and said Jpump, andahydraulic motor carried by said shaft 1n yaxial alignment therewith andoperatively connected to said tilting means, and controls respectivelyfor said clutchand said hydraulic.motorzmounted exterior to said casing.

7. A rotary .machine for surfacing concrete comprising a'casing havingaclosed chamber therein, said casing having 'an upper side and alowerside, apower plant mounted on said upper side having .athrottletherefor, said power plant having aclosed Ijunction with said chamber, ahollow .driven shaft mounted on said .lower side .in general alignmentwith lsaid power plant and la housing at the lower end of said shafthaving a closed Vpocket therein, radially Vpositioned vblade assembliestiltably mounted yon said lhousing and extending into said pocket, acommon tilting means for said blades extending from said `blades intosaid shaft, a drive train in said chamber having a connection to saidpower plant `in said closed junction and having a connection to saidshaft within said chamber, a clutch operatively connected betweenopposite .ends of said drive train and mounted within said chamber, ahydraulic pump carried by the casing in said chamber and a pumpactuating means operatively connected xbetween said drive train and saidpump, a hydraulic motor carried "by said shaft in axial alignmenttherewith and .Y

operatively connected to said tilting means, a `handle on the casing andcontrols on the handle connected respectively to said clutch, saidhydraulic motor and said power plant control.

'8. A rotary machine lfor surfacing concrete comprising a casing forminga closed chamber, a power plant on the casing having a drive shaftextending into the chamber, a hollow driven shaft rotatably -mounted inthe chamber at the lower side of the lcasing, a drive train between thedrive shaft and the driven shaft, a housing below the casingmounted onsaid driven shaft for rotation thereby, aplurality of blades extendingradially outwardly from thehousing and having an adjustable tiltableymounting thereon, tilting means in the casing secured to theblades, acommon adjusting element interconnecting said blades and having .anactuator extending through said driven shaft `into said casing, saidactuator comprising an axial chamber in .the `driven shaft, a pistonreciprocatably mounted :in the axial -cbamber and a piston rod thereoninloperating engagement with said tilting means, a uid passage .fromsaid axial chamber throughthe vupperfportion of the driven shaft andterminating at the-upperf'end thereof, a'fluid connection swivellymounted at the upper end ofthe driven shaft in communication with saidduid passage, an operating handle on the casing having a'hand holdthereon, a uid pump on the operating handle, an actuating lhandleconnected to the pump and movably mounted on the operating handleadjacentsaid hand hold, and a'uid line having a relatively `iixedlocation, .one end of said line having a stationary connection to thepump and the other end of said line having a connection to fthelluidtting .at a fixed location within thechamber, and aimanual releasefluid return in the lfluid'line located 0n the operating handle.

9. A krotary machine for surfacing concrete comprising a casing forminga closed chamber, a power plant on the casing having a drive shaftextending into the chamber, a hollow driven shaft rotatably mounted inthe chamber at the Vlower side of the casing, a drive train between thedrive shaft and the driven shaft, a housing below the casing -mountedonsaid driven shaft for rotation -lthereby, a. pluralityof Abladesextending radially outwardly from ythe housing and Vhaving an adjustabletiltable mounting 'thereon, tilting means in the casing secured to ytheblades, a common adjusting element interconnecting ysaid blades and`having an actuator extending through said driven shaft into saidcasing, said actuator comprising an axial chamber in the driven shaft, apiston reciprocatably mounted in the axial chamber and a piston rod'thereon in operating engagement with said tilting means, a uid passagefrom said'axial chamber through the upper portion .ofthe driven shaftand terminating at `the upper end thereof, a uid connection swivellymounted at the -upp'er end of the driven shaft in communication withsaid fluid passage, an operating handle on the casing having a yhandhold thereon, a fluid pump on the operating handle, an actuating handleconnected to the pump and movably mounted on the operating handleadjacent said hand hold, and a Huid line having a relatively xedlocation, one end of said Lline having a stationary connection 'to the`pump and the other end of said line having a connectiontothe duidfitting at a iixed location within the chamber, and a vmanual releasefluid return in the fluid line vlocated on the operating handle, aclutch in said drive train and within said closed chamber, said clutchhaving a pair of relatively movable clutch halves, a clutch actuatinglever on the operating handle adjacent said hand hold, and a connectionfrom tbe clutch actuating lever extending through said .operating.handle to one of said clutch halves whereby to .enable actuation of theclutch at the same relative location as that occupied by the actuatinghandle.

10. -A rotary machine for surfacing concrete comprising a casing,forming a chamber, a hollow driven shaft extending below the casing, aVhousing attached to the driven shaft, and handle extending laterallyoutwardly and upwardly from the casing, a power plant mounted on the.casing and a drive shaft for the power plant extending into the casing,a power train in the chamber interconnecting the drive shaft and thedriven shaft, -a plurality Vof surfacing blades extending radiallyoutwardly from said housing and tiltably mounted on longitudinal Vaxesthereof in said housing and tilting means interconnecting said bladesadapted to alter the adjustment of said blades, said casing including areservoir of hydraulic liquid associated with said chamber, a pumpcarried by the casing connected to saidreservoir, a pump drivingmechanism operably connected between said power train and the pump, anaxial chamber in the driven shaft, a hydraulic motor in the axialchamber connected through said driven shaft to said tilting meansadapted to effect a tilt adjustment in said blades, a hydraulic valvecarried by the casing connected to said pump and having a man'- ualcontrol therefor on said handle, a hydraulic connection from said valveto said hydraulic motor, and a hygamers draulic return connection tosaid reservoir from said valve adapted to discharge hydraulic liquidfrom said motor, a bracket element on the casing for said handle, acomplementary bracket element on the handle, a series of aperturesrespectively on said bracket element having a plurality of positions ofalignment, and a pin engageable with aligned apertures in each of saidplurality of positions of alignment.

1l. A rotary machine for surfacing concrete comprising a casing forminga chamber, a hollow driven shaft extending below the casing, a housingattached to the driven shaft, and a handle extending laterally outwardlyand upwardly from the casing, a power plant mounted on the casing and adrive shaft for the power plant extending into the casing, a power trainin the chamber interconnecting the drive shaft and the driven shaft, aplurality of surfacing blades extending radially outwardly from saidhousing and tiltably mounted on longitudinal axes thereof in saidhousing and tilting means interconnecting said blades adapted to alterthe adjustment of said blades, said casing including a reservoir ofhydraulic liquid associated with said chamber, a pump carried by thecasing connected to said reservoir, a pump driving mechanism operablyconnected between said power train and the pump, an axial chamber in thedriven shaft, a hydraulic motor in the axial chamber connected throughsaid driven shaft to said tilting means adapted to effect a tiltadjustment in said blades, a hydraulic valve carried by the casingconnected to said pump and having a manual control therefor on saidhandle, a hydraulic connection from said valve to said hydraulic motor,and a hydraulic return connection to said reservoir from said valveadapted to discharge hydraulic liquid from said motor, a guard ringsurrounding outer ends of said blades, said ring comprising separablesubstantially sernieircular halves and releasable connections betweenends of said halves, legs on each said half and releasable connectionsbetween said legs and the casing mounting said ring below the casing ata location adjacent the outer ends of said blades.

12. A rotary concrete surfacing machine comprising a casing forming achamber, a power plant on said casing having a drive shaft extendinginto the casing, a bearing on the lower side of the casing having adriven shaft rotatably mounted therein, a gear train in said chamberincluding rotating drive elements and rotating driven elementsconnecting said drive shaft and said driven shaft and a clutch in saidgear train interconnecting said drive elements and said driven elementswhen engaged, a part of said chamber forming a reservoir for a supply ofliquid, a reciprocating hydraulic pump connected to said reservoir, oneof said rotating drive elements having a peripheral cam face, a leverpivotally mounted between said pump and said cam face to reciprocate thepump while said cam face is rotating, a hydraulic valve device connectedto said pump and a valve element in the valve device having a manuallyoperating element extending l outside said casing, a housing mounted onsaid driven shaft, blades tiltably mounted on said housing onlongitudinal axes thereof and in radially outwardly extending position,tilting means on said blades extending radially with respect to theaxes, a common adjusting drive for said tilting means and areciprocating hydraulic motor having a hydraulic liquid supplyconnection to said valve device and a mechanical output element on saidlast named hydraulic motor operatively connected to said tilting means.

13. A rotary concrete surfacing machine comprising a casing having achamber therein, a power source carried by the casing, a concretesurfacing means comprising a housing, a hollow driven shaft xed to saidhousing and rotatably mounting the same on the casing and a set ofhorizontally rotating blade assemblies separately rotatably mounted onhorizontal axes on the housing and extending radially outwardlytherefrom, a tilt adjusting means having a portion thereof in thehousing common to all said blade assemblies and in operable engagementwith said blade assemblies, said tilt adjusting means having a portionthereof extending through the hollow driven shaft into said chamber, agear train including rotating drive means operatively connected to thepower source and rotating driven means operatively connected to thehollow driven shaft and a clutch connecting said rotating driven meanswhen engaged, a separate actuator operatively connected to said tiltadjusting means, a power take-off operatively connected to said rotatingdrive means, and a manually operable blade tilting control devicearranged to selectively connect said power take off to said actuatorwhereby to ei'ect selective power-actuated adjustment of said bladesindependently of rotation of said hollow driven shaft and at the will ofthe operator.

References Cited in the file of this patent UNITED STATES PATENTS2,198,929 Whiteman Apr. 30, 1940 2,277,389 Conway Mar. 24, 19422,351,278 Mathews June 13, 1944 2,446,028 Sponseller July 27, 19482,468,981 Hutman May 3, 1949 OTHER REFERENCES Engineering News-Record,page 52, May 19, 1955.

